Strontium titanate and solid solutions on its base

Ceramic specimens of solid solutions of the SrTiO3-BaTiO3, SrTiO3-CaTiO3 systems are synthesized. X-ray phase analysis and measurements of their dielectric properties in 4.2-200 K range are carried out. Exceptea expressed maximum permittivity wkly expressed anomalies are found at temperature epsilon(T) dependence, their concentra tional dependence is studied. It is established that Curie point of strontium titanate is in the range of 100-112. 5 K and that pure SrTiO3, besides the high-temperature phase transition, has a series of low-temperature phase transitions, the position of which, probably, obeys the dependence Tsub(ptt)=Tsub(0)N (N-an integer, T0=12.5 K)